Contractual Weight Values and S-Curves

The EPC Project Dilemma

Khonopc has recently been tasked to check the Schedule and its progress reports on an EPC Project. The Client had quested to have the Schedule resource/cost loaded. The Contractor’s Planner added some names and roles in the resource tab and the Client planner approved it.

Less than a month later, both Client and Contractor realised that the progress report produced and calculated through P6 did not seem correct. We were thereafter requested to assist in resolving the issue!

The Standard Workflow

1. The Requirement: The Client or Contractor requests a resource/cost-loaded Schedule.
2. The Goal: The Client or contractor wants the roll up progresses (plan and actual) in the planning software (P6).
3. The Execution: The contractor’s planner does the resource / cost loading (rightly or incorrectly). After the Schedule approval, it gets used for progress reporting!.
4. The Roll-up Calculation: P6 uses the input data for calculations. Regardless of whether the team understands the weight values, the software will roll up the progress.

Where the Conflict Begins

Up to this step, there might not be any issue. The problem comes when there is a set of contractualcontractual (or instructed) weight values which the Client had instructed the Contractor to utilise on the software! It should be noted that, if resource loading was correctly performed, the S-Curves would have been accurate as well!

5. Instructions: The client requests the following weight values (E, P, C, C) to be applied in the Schedule
6. The Manipulation: Planners often have no choice but to manipulate budgeted units/costs to force the schedule to meet these requested percentages.
7. The Consequence: By changing the budgeted units (or cost), the S-Curves for Engineering, Procurement, and Construction are fundamentally altered.
8. The Impact: When an S-Curve is wrong, the visibility of the project’s actual delivery and completion date disappears.

Example of enforced weight values

The Result: Project Failure

The Solution

When a Client enforces weight values that differ from cost/effort-based logic, it becomes impossible to maintain an accurate resource-loaded schedule within P6.

In this scenario, progress calculations must be done outside the scheduling software. Attempting to force them inside will corrupt your budgeted units, your costs, and your S-Curves, leading to a management system that cannot be trusted.